Metamath Proof Explorer


Theorem slemuld

Description: An ordering relationship for surreal multiplication. Compare theorem 8(iii) of Conway p. 19. (Contributed by Scott Fenton, 7-Mar-2025)

Ref Expression
Hypotheses slemuld.1
|- ( ph -> A e. No )
slemuld.2
|- ( ph -> B e. No )
slemuld.3
|- ( ph -> C e. No )
slemuld.4
|- ( ph -> D e. No )
slemuld.5
|- ( ph -> A <_s B )
slemuld.6
|- ( ph -> C <_s D )
Assertion slemuld
|- ( ph -> ( ( A x.s D ) -s ( A x.s C ) ) <_s ( ( B x.s D ) -s ( B x.s C ) ) )

Proof

Step Hyp Ref Expression
1 slemuld.1
 |-  ( ph -> A e. No )
2 slemuld.2
 |-  ( ph -> B e. No )
3 slemuld.3
 |-  ( ph -> C e. No )
4 slemuld.4
 |-  ( ph -> D e. No )
5 slemuld.5
 |-  ( ph -> A <_s B )
6 slemuld.6
 |-  ( ph -> C <_s D )
7 1 4 mulscld
 |-  ( ph -> ( A x.s D ) e. No )
8 1 3 mulscld
 |-  ( ph -> ( A x.s C ) e. No )
9 7 8 subscld
 |-  ( ph -> ( ( A x.s D ) -s ( A x.s C ) ) e. No )
10 9 adantr
 |-  ( ( ph /\ ( A  ( ( A x.s D ) -s ( A x.s C ) ) e. No )
11 2 4 mulscld
 |-  ( ph -> ( B x.s D ) e. No )
12 2 3 mulscld
 |-  ( ph -> ( B x.s C ) e. No )
13 11 12 subscld
 |-  ( ph -> ( ( B x.s D ) -s ( B x.s C ) ) e. No )
14 13 adantr
 |-  ( ( ph /\ ( A  ( ( B x.s D ) -s ( B x.s C ) ) e. No )
15 1 adantr
 |-  ( ( ph /\ ( A  A e. No )
16 2 adantr
 |-  ( ( ph /\ ( A  B e. No )
17 3 adantr
 |-  ( ( ph /\ ( A  C e. No )
18 4 adantr
 |-  ( ( ph /\ ( A  D e. No )
19 simprl
 |-  ( ( ph /\ ( A  A 
20 simprr
 |-  ( ( ph /\ ( A  C 
21 15 16 17 18 19 20 sltmuld
 |-  ( ( ph /\ ( A  ( ( A x.s D ) -s ( A x.s C ) ) 
22 10 14 21 sltled
 |-  ( ( ph /\ ( A  ( ( A x.s D ) -s ( A x.s C ) ) <_s ( ( B x.s D ) -s ( B x.s C ) ) )
23 22 anassrs
 |-  ( ( ( ph /\ A  ( ( A x.s D ) -s ( A x.s C ) ) <_s ( ( B x.s D ) -s ( B x.s C ) ) )
24 0sno
 |-  0s e. No
25 slerflex
 |-  ( 0s e. No -> 0s <_s 0s )
26 24 25 mp1i
 |-  ( ph -> 0s <_s 0s )
27 subsid
 |-  ( ( A x.s D ) e. No -> ( ( A x.s D ) -s ( A x.s D ) ) = 0s )
28 7 27 syl
 |-  ( ph -> ( ( A x.s D ) -s ( A x.s D ) ) = 0s )
29 subsid
 |-  ( ( B x.s D ) e. No -> ( ( B x.s D ) -s ( B x.s D ) ) = 0s )
30 11 29 syl
 |-  ( ph -> ( ( B x.s D ) -s ( B x.s D ) ) = 0s )
31 26 28 30 3brtr4d
 |-  ( ph -> ( ( A x.s D ) -s ( A x.s D ) ) <_s ( ( B x.s D ) -s ( B x.s D ) ) )
32 oveq2
 |-  ( C = D -> ( A x.s C ) = ( A x.s D ) )
33 32 oveq2d
 |-  ( C = D -> ( ( A x.s D ) -s ( A x.s C ) ) = ( ( A x.s D ) -s ( A x.s D ) ) )
34 oveq2
 |-  ( C = D -> ( B x.s C ) = ( B x.s D ) )
35 34 oveq2d
 |-  ( C = D -> ( ( B x.s D ) -s ( B x.s C ) ) = ( ( B x.s D ) -s ( B x.s D ) ) )
36 33 35 breq12d
 |-  ( C = D -> ( ( ( A x.s D ) -s ( A x.s C ) ) <_s ( ( B x.s D ) -s ( B x.s C ) ) <-> ( ( A x.s D ) -s ( A x.s D ) ) <_s ( ( B x.s D ) -s ( B x.s D ) ) ) )
37 31 36 syl5ibrcom
 |-  ( ph -> ( C = D -> ( ( A x.s D ) -s ( A x.s C ) ) <_s ( ( B x.s D ) -s ( B x.s C ) ) ) )
38 37 imp
 |-  ( ( ph /\ C = D ) -> ( ( A x.s D ) -s ( A x.s C ) ) <_s ( ( B x.s D ) -s ( B x.s C ) ) )
39 38 adantlr
 |-  ( ( ( ph /\ A  ( ( A x.s D ) -s ( A x.s C ) ) <_s ( ( B x.s D ) -s ( B x.s C ) ) )
40 sleloe
 |-  ( ( C e. No /\ D e. No ) -> ( C <_s D <-> ( C 
41 3 4 40 syl2anc
 |-  ( ph -> ( C <_s D <-> ( C 
42 6 41 mpbid
 |-  ( ph -> ( C 
43 42 adantr
 |-  ( ( ph /\ A  ( C 
44 23 39 43 mpjaodan
 |-  ( ( ph /\ A  ( ( A x.s D ) -s ( A x.s C ) ) <_s ( ( B x.s D ) -s ( B x.s C ) ) )
45 slerflex
 |-  ( ( ( B x.s D ) -s ( B x.s C ) ) e. No -> ( ( B x.s D ) -s ( B x.s C ) ) <_s ( ( B x.s D ) -s ( B x.s C ) ) )
46 13 45 syl
 |-  ( ph -> ( ( B x.s D ) -s ( B x.s C ) ) <_s ( ( B x.s D ) -s ( B x.s C ) ) )
47 oveq1
 |-  ( A = B -> ( A x.s D ) = ( B x.s D ) )
48 oveq1
 |-  ( A = B -> ( A x.s C ) = ( B x.s C ) )
49 47 48 oveq12d
 |-  ( A = B -> ( ( A x.s D ) -s ( A x.s C ) ) = ( ( B x.s D ) -s ( B x.s C ) ) )
50 49 breq1d
 |-  ( A = B -> ( ( ( A x.s D ) -s ( A x.s C ) ) <_s ( ( B x.s D ) -s ( B x.s C ) ) <-> ( ( B x.s D ) -s ( B x.s C ) ) <_s ( ( B x.s D ) -s ( B x.s C ) ) ) )
51 46 50 syl5ibrcom
 |-  ( ph -> ( A = B -> ( ( A x.s D ) -s ( A x.s C ) ) <_s ( ( B x.s D ) -s ( B x.s C ) ) ) )
52 51 imp
 |-  ( ( ph /\ A = B ) -> ( ( A x.s D ) -s ( A x.s C ) ) <_s ( ( B x.s D ) -s ( B x.s C ) ) )
53 sleloe
 |-  ( ( A e. No /\ B e. No ) -> ( A <_s B <-> ( A 
54 1 2 53 syl2anc
 |-  ( ph -> ( A <_s B <-> ( A 
55 5 54 mpbid
 |-  ( ph -> ( A 
56 44 52 55 mpjaodan
 |-  ( ph -> ( ( A x.s D ) -s ( A x.s C ) ) <_s ( ( B x.s D ) -s ( B x.s C ) ) )